Storage battery electrode and method of making



Jan. 20, 1953 J. B. BRENNAN STORAGE BATTERY ELEcTRoDE AND METHOD oF MAKING Filed March 25, 1950 INV EN TOR.

22 Fia?. QQ@- Patented Jan. I20, 129572 UNITED STATES PATENT OFFICEr STORAGE BATTERY Emoment: AND

METHOD oF MAKING Joseph B. Brennan, Cleveland-.Ohio Application March 2s, 195o, seriarNo. 151,405

(Cl. 13e- 28)- This invention relates toa storage battery elec trode and method of makngsame;

The electrode of this invention is characterized by the fact that a' porous electrolytically inert structure supports andretains active materials in conductive relationship with a porous contacting conductor of coherent and-adherent metal.

This application is a continuation in part' of my pending application Serial No.l 40,919, filed July 27, 1948.

Referring to the drawings which accompany this sp'ecication:

Figure 1 is an isometric section of anelectrode according' to this invention'.

Figure 2f is a copy of Figure 4' of the drawings of *myv pending application SerialfNo, 40,919; led July 27, 1948, and represents'aslightly modined form of electrode according to this invention.

Figure 1 represents an isometric section of an electrode according to this invention wherein I represents a perforated strip as of asbestos paper or asbestos board exaggerated in thickness impregnated with active material 4, having the perforations 3 therethru, having a porous spray deposited coating of metal 2 thereover, which spray deposited coating extends into and thru the perforations 3 so as to conductively unite the coating at intervals. The terminal 5 is attached by welding or other means to the electrode body at 6. 1, Figure 1 represents a partial section of an overlay of porous spray deposited particulate dielectric to act as an exterior separator and support for the electrode of this invention, bonded to said electrode and permeable throughout by the electrolyte.

Referring to Figure 2 of the drawings accompanying this specification, 24 is a layer as of asbestos paper or board impregnated with active material 2l and coated With porous metal layers 20 having a terminal 22 attached thereto by means of extruded rivets 23.

To make the electrode of this invention I impregnate for example porous asbestos plates having a porous conductive coherent coating of particulate nickel either sintered thereon or spray deposited with molten nickel particles thereover with nickel nitrate solution by immersing the metalized asbestos plates in a nickel nitrate solution and thereafter immersing the plate so previously impregnated with nickel nitrate in a KOH concentrated solution, with the result that the pores of the base asbestos material and the porous metal enclosure or coating are lled with nickelous hydroxide active material. which is conductive when activated, and shows capacity in proportion to the amount of porous space ll'ed'with nickelous hydroxide therein.

It is possible tol secure a capacity inv a plate having electrolyticallyinertfporous base material, such as asbestos iibrous` sheet material coated with porous conductive particulate spray deposited nickel equalin capacityto that procurable in an all porousnickel plate of 'equal volume and of much greater nickel content'.` Other porous base materials suitable"forsuchl use in'makng battery plates'are' ceramic'materials, such Aas alkali resistant breglas's or porous A1203 or porous carbon or` porous polystyrene particulate membranes, or porous fabrics inert to the electrolyte, or porous-resinous, or porous fused rceramic base materials. y

Thus I am; able` toY makez a lighteryhigher capacity electrode than has` heretoforey beenr made 'by the use of cheap materials in combination with only a much smaller amount of conductive metal.

It is preferable that the porous metal coating adhere to the 'base asbestos material so as to secure a structurally strong electrode. However, it is possible to secure this adherence by an assembly made up of the porous base material and the porous nickel material in strip form, being applied as by welding or other mechanical fastening means to the asbestos.

It is also contemplated according to this invention to enclose the molten particulate metal coated porous base material electrode in a coating of porous particulate dielectric material, such as of spray deposited polystyrene or other inert synthetic porous dielectric material to make a unitary electrode and separator. For example, I take a piece of porous asbestos strip .015 thick and coat it continuously on both sides and about the edges thereof with a porous spray deposited coating.' of nickel about .005 thick and thereafter pass this strip through nickel nitrate solution to impregnate thoroughly all the pores of the asbestos and'v porous nickel layer, and thereafter pass this stripthru KOH solution continuously to convert thenickel nitrate in the pores of the porous asbestos: and porous nickel coating to nickelous hydroxide, and then cut up this strip into 5" lengths and weld a nickel coated terminal thereto, and activate this plate by cycling electrically, whereupon I obtain a capacity of 1.5 ampere hours in such a plate assembled with two negative identically made plates, but activated with cadmium oxide in the pores thereof. This is as much capacity as I can get with an all porous nickel plate of equal volume.

The structure and treatment and impregnation 3 of the negative plates is carried out in the same Way as the positive plates, the only difference being that the active materials with which the `plates are impregnated is either activated cadmium oxide, or iron oxide, or zinc oxide, or silver oxide, or combinations of these or other oxides suitably useful as active negative materials in an alkaline cell.

In any case, according to my invention I secure an electrode wherein the active materials are supported by a porous plate of electrolytically inert material containing the active material in the interstitial pores thereof in unitary structure Vperforated or used in strip form and joined together as by wel-ding or s-praying.

By electrolytically inert base material I mean a self-supporting piece, strip or layer of such material which Will not disintegrate or break up in .use or in the processing involved. in making electrodes according to this invention.

v Having described my invention, what I claim 1. A storage battery electrode comprising a particulate porous carbon plate impregnated with an active battery oxide and having a coating of porous particulate batt-ery metal thereover.

2. A storage battery electrode comprising a unitary porous particulate carbon plate, the interstitial pores of which are filled with porous active nickelous oxid and hydroxide having a layer of porous particulate nickel thereover.

3. A storage battery electrode as in claim 2, wherein the impregnating compound includes cadmium oxide.

4. Method of making a storage battery electrode by impregnating a porous electrolytically inert support with nick-el nitrate, converting said nickel nitrate to nickelous hydroxide while included in the pores of said support and thereafter applying a porous metallic eleotrolytic membrane thereto in conductive unitary relationship.

5. Method of making a storage battery electrode by applying a porous conductive metallic coating to a porous electrolytically inert support and thereafter impregnating the so coated support with a nitrate of active battery material and thereafter converting said nitrate to an active battery material.

i lJOSEPH B. BRENNAN.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS 

1. A STORAGE BATTERY ELECTRODE COMPRISING A PARTICULATE POROUS CARBON PLATE IMPREGNATED WITH AN ACTIVE BATTERY OXIDE AND HAVING A COATING OF POROUS PARTICULATE BATTERY METAL THEREOVER. 